This paper considers a Lotka-Volterra model with time delays and delay dependent parameters. The linear stability conditions are obtained with characteristic root method. The Hopf bifurcation is demonstrated. Using normal form theory and center manifold theory, Some explicit formulae for determining the stability and the direction of the Hopf bifurcation periodic solutions are derived. Finally,...

The Hopf bifurcation in slow-fast systems with two slow variables and one fast variable has been studied recently, mainly from a numerical point of view. Our goal is to provide an analytic proof of the existence of the zero Hopf bifurcation exhibited for such systems, and to characterize the stability or instability of the periodic orbit which borns in such zero Hopf bifurcation. Our proofs use...

This paper deals with the qualitative analysis of a disease transmission delay induced prey predator system in which disease spreads among the predator species only. The growth of the predators’ susceptible and infected subpopulations is assumed as modified Leslie–Gower type. Sufficient conditions for the persistence, permanence, existence and stability of equilibrium points are obtained. Globa...

We present an unfolding of the codimension-two scenario of the simultaneous occurrence of a discontinuous bifurcation and an Andronov-Hopf bifurcation in a piecewise-smooth, continuous system of autonomous ordinary differential equations in the plane. We find that the Hopf cycle undergoes a grazing bifurcation that may be very shortly followed by a saddle-node bifurcation of the orbit. We deriv...

This paper is devoted to the study of the stability of limit cycles of a nonlinear delay differential equation with a distributed delay. The equation arises from a model of population dynamics describing the evolution of a pluripotent stem cells population. We study the local asymptotic stability of the unique nontrivial equilibrium of the delay equation and we show that its stability can be lo...

The steady state and dynamic behavior of two-phase systems in physical equilibrium is investigated. The autonomous and non-autonomous systems are considered. The pseudo-arclength bifurcation technique reveals steady state multiplicity patterns not previously observed, including isola and mushroom patterns. It is shown that degenerate singular points of codimension 2, which violate the non-singu...

The strong coupling, multivariate, and nonlinear characteristics of the mathematical model a doubly-fed induction generator (DFIG) make it challenging to analyze bifurcation category DFIG. Therefore, in this study, we developed method for analyzing DFIG via topologically equivalent dimensionality reduction neighborhood values based on central manifold theorem realized discrimination Hopf type W...

Tensor operators in graded representations of Z2−graded Hopf algebras are defined and their elementary properties are derived. WignerEckart theorem for irreducible tensor operators for Uq[osp(1 | 2)] is proven. Examples of tensor operators in the irreducible representation space of Hopf algebra Uq[osp(1 | 2)] are considered. The reduced matrix elements for the irreducible tensor operators are c...

In this paper, we consider the direction and stability of time-delay induced Hopf bifurcation in a delayed predator-prey system with harvesting. We show that the positive equilibrium point is asymptotically stable in the absence of time delay, but loses its stability via the Hopf bifurcation when the time delay increases beyond a threshold. Furthermore, using the norm form and the center manifo...